Automatic draft controlling device



1932- w. A. HANNUM 1,870,505

AUTOMATIC DRAFT CONTROLLING DEVICE Filed Oct. 23, 1950 2 Sheets-Sheet l Fig.2.

INVENTOR.

WzZ/zbm A. f/amzz/m ATTORNEY.

1932- w. A. HANNUM 1,870,505

AUTOMATIC DRAFT CONTROLLING DEVICE Filed Oct. 23, 1930 2 Sheets-Sheet 2 Fly. 3. E5. 4.

I N VEN TOR.

h zl lz'am A Hamil/272 1 1 v i I ATTORNEY.

Patented Aug. 9, 1932 Fri-meat app-messsemester23,1932). 'sem'r'myisojsa.

The 5 present invention relates to die it control -deviees and more :c-p articu-larly to means for controlling the entrano'eof air into turnaees; stoves, fire boxes, boilers or the like.

-1 Air obj eat of this invention-is to. provide an autonfati'lilly operated airc'ontr'olling device which may be "secured to conventional furmaze er boiler Without interfering withthe present parts of the furnace or boiler and -m'which will c'ontrolth'equantity of fresh *air admitted 'to the furnace from the exterior of "the buildingregardless of the pressure of the atmosphereof air inside of thebuilding.

Another object of this invention is to proiavide a'device'of this kind with a'balance'd valve or daniperwhich is automatically conbl'OilGClbY the amount of suction and pressure exerted from the exterior of the-building. v

'The above and various otherobjects and '20 advantages of this invention Will in part be d'esoi'ib'edin and in part be un'd'erstoodfrom the'rouowin' detailed description of th'eprese'nt preferredembodiment, the same being illustrated in the accompanying drawings,

5 wherein Figure 1 is horizontalsectibnal View t'akensubstantially through the center of a deviceeenstructeuaccording to the referred einb ofliinent ef-this invention; 7

Figure 2 is a -detail side elevation of the device; l

I Figure 3 a seet-ional'view'taken'on-the line-3 3 of Fi'gure 1; H 'Figure isa seetio'nal viewtakenon the 35 l-i'n'e i' L of Figure 1 I Figu e '5fis' a't' rtie-alsectional-view taken substantially on" the line 5 5" of Figure e Figures enlarged fragmentar sectional view showing in detail the method of supporti'n "the "air Controlling member, and -Figureg is a sectional view showin a modification of the device. v

"Refer-rind to the drawings wherein like numerals elreferehce designate corres ond- 45 in g -part's' thi'oughout*the"several Views, the numeral '10 designates generally a furnace or heating member Whih is provided at p the desired point "with anash door 13"v'thic'his i hiugedlysecured to the furnacebr heating unit 10 anuengages against assets-endin bbXingprfiah-ge 11. In the heztting units at present available, the air used in the-combustion of the fuel is drawn from the interior of the building and this use of the air Within the buildi-n-g'causes a; reduction bf the air pressure within the'buildiiig and the air'o'utsideojt'the'building seeps into the interior through ciaoks-or the like so asto-eqi'ialiie thepressure Within-theinterior and exterior of, the building; 7

Whilenumerous-devices have been devised for taking the air from the exteriorof the building 'fd'IlCl @passing it about the heating shell orunit-,these' deviceshave for their main object the provisionof fresh air which is drawn about the heating shell for use Within 'therooms or interior of the building, but this flair-is not use'd for 'COIH'bUSlLlOHPHlPOSGS or passed into --the fire box of theheating unit.

In order, therefore, to provide adequate jmea-ns foripassing fresh 'air'into the firebox, 'Ihave-provided-an air conduit 12 which is -in'coinmunication at one end with the atmosphere outside of the building. The other or inner end of the efonduit 12 has securedthereto a heat controlling unit generally'designated'as 14, the air controlling unit 14 eoniprising a boxing of any desired configuration which isiprovided at the outer end thereof with 'aupartition 'or Wall 15, the'wall 5 -15 having'a'pair of openings 16 therethrough, oneof the openingslG and 16 beingpositioned below 'the-center of the partition 15 and the-other opening being above thecenter and oppositely from the vertical, center to the lower opening thereby sproviding' a pairof staggered openings from the conduit 12 The controlling unit lfl is alsoproyided with an inner'wallli' which is also provided with upper andlower' staggered openings '18 and l8 therethroug-h Whi'ch 'are positioned oppositely ifr'oih the'openings I6 in the outer walljlj,

Abalenfe'ecl1daniper is is mainl -mums- "ed on a pa'ir ofadjustabletrunnidnsfll) w'tliieh "are 'seeureu tatheinner and enter will sienbeis l5, respectiyelyflihdexte'ndfint'o the bod'yof'th'e daihper 19fsoas ad-swingeb'ly support'the' dam en within th'e'unit 1e.

ree-(sepsis ends 'of-th'e damper 1a he pererably beveled, as at 21, and engage, when in closed position, against the inner surface of the walls of the air controlling unit 14 and a seat 22 is secured to the inner walls of the air controlling unit 14 and the damper 19 is adapted to also engage against the seats 22, the seats 22 cooperating with the inner surface of the unit so as to limit the swinging movement of the damper.

The dampers 19 are also provided with threaded pins 23 which are offset slightly from the axial center thereof and a threaded weight 24 is threadedly positioned on the bolts 23, the weights 24 being adapted to be adjusted so as to permit the damper 19 to be balanced within the unit 14. The damper 19 is provided with the balancing weights 24 on the opposite faces thereof so that a perfect balance may be secured by adjusting the weights 24 inwardly or outwardly.

The air controlling unit 14 at the opposite sides thereof is preferably divided longitudinally so as to provide an upper portion 25 and a lower portion 26, the upper portion 25 being provided with a rabbet 27 which is engaged by a suitable rabbet in the lower portion 26. The unit 14 is also provided with a centrally disposed artition or wall 28 which extends longitu inally of the unit, the wall 28 being provided with an opening 29 extending substantially centrally therethrough for loosely receiving the damper plate 19 and so as to permit the damper 19 to have relative rocking movement within the unit 14.

The inner end of the unit 14 is provided with a pair of vertically disposed guides 30 on each side thereof in which is slidably mounted a'vertically slidable damper or closure plate 31. The plate 31 cooperates with the inner partition 18 so as to provide a mixing chamber 32 within which the air passing inwardly through the air controlling unit 14 is adapted to be mixed and passed outwardly of the inner end of the unit 14. The extent of opening of the unit 14 is controlled by the vertical movement of the sliding plate 31.

The chamber 32 is provided at the upper surface thereof with an elliptical flange 33 upon which a closure plate 34 is positioned. Thisfla nge 32 provides an outlet from the air controlling unit 14 so as to permit the air within the air controlling unit 14 to be passed into the interior of the building and serves as a by-pass for the air.

In new furnaces, it is desirable to secure the air controlling unit 14 directly to the lower shell or base of the furnace or boiler as disclosed in Figure 7. However, where furnaces have already been installed and are not especially equipped to receive the air controlling unit as disclosed in Figure7, the inner end of the air controlling unit 14 is provided with a hinged conduit 35 which is hingedly secured to the unit 14 by means of conventional hinges 36 or the like.

The conduit 35 is preferably of tapering construction, being provided at the outer end thereof with an opening 37 and one face of the conduit 35 is preferably flat and coplanar with one wall of the air controlling unit 14. The flat side of the conduit 35 is adapted to engage against a packing plate 38 which engages against the outer edge of the flange 11 of the furnace 10.

Adjacent the inner end of the conduit 35 there is provided a flanged passage 39 which communicates with the passageway 40 in the furnace 10 which is conveniently used for removal of ashes from the base of the furnace. Through the use of the hinged conduit 35, it'is possible to adapt the air controlling unit 14 to any furnace or boiler without in any way interfering with the present parts, of

the heating member, the conduit 35 being so In the use of this device, the air controlling unit 14 is adapted to be secured to the conduit 12 which is in communication at the outer end thereof with the atmosphere exterior-1y of the building and the closure door 31 is adapted to be moved upwardly of the unit 14 so as to provide the desired opening for the air to pass through the conduit 35 and into the furnace; When the vertically movable, door, 31 is pulled upwardly, the suction from .the furnace 10 will swing the balancing damper 19 into open position and thereby draw the air through the passageways 16 and 18, the air passing inwardly of each face of the damper 19 so as to substan tially cushion the rocking movement of the damper 19 within theunit 14.

When the wind pressure on the exterior of the building becomes excessive, the force of air passing through the opening 16 will have a tendency to close the damper 19 or to swing it into a position so as to limit the passage of air up to the capacity of the furnace 10 to receive the fresh air. Through the use of thisdevice, the air used as combustion by the furnace will at all times be fresh air which is drawn from the exterior of the building and if desired, the fresh air may be passed about suitable preheating chambers before entering the furnace 10 so that when the air strikesthe grates, it will be substantially heated air instead of cold air.

It will also be obvious from the foregoing that the outlet 33 may be connected to the shell of the furnace 10 so as to permit the mg an air controlling'unit which in addition to controlling the air entering the fire box of the heating unit, the air controlling unit will also control the quantity of air passing into the preheating or air shell of the heating unit. In the event there should be any back pressure from the furnace, the back pressure would cause the damper 19 to swing immediately into closed position.

It is, of course, understood that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims.

I claim 1. An air controlling device of the character described, comprising a casing, an inner transverse wall mounted in the casing and having staggered openings therethrough, a longitudinally disposed wall mounted in the casing and engaging against said transverse wall, said longitudinally disposed wall having a longitudinally disposed opening therethrough, a rockable closure member mounted in the casing and engaging within said longitudinally disposed opening, said casing and said transverse wall having staggered openings therethrough whereby to permit the passage of air through the casing on opposite sides of said closure member and coactively cushioning the movement of said closure member, adjustable balancing means carried by said closure member for adjusting the balance thereof, and means for connecting the casing to a heating unit.

2. An air controlling means comprising a casing, an inner divided wall, said casing having a pair of openings in each end, one opening of each pair being on one side of the inner wall below the center thereof and the other opening being on the other side of the inner wall and above the center thereof, the openings in one end wall being opposite from the openings in the other wall, and a suction operated damper swingably mounted between the division of the inner wall.

3. An air controlling means comprising a casing, an inner wall including an upper and a lower wall member having their abutting edges spaced apart, a substantially balanced damper swingably mounted between said upper and lower wall members, said casing having openings in each end thereof so disposed as to swing the damper in open position by suction drawing air through the casing, and to close the damper by air pressure in excess of the suction.

4. An air controlling means comprising a casing, an inner wall mounted in substantially the longitudinal center of the casing, said inner wall having a longitudinally extending slot therethrough in substantially the center thereof, a damper swingably mounted in said slot, means for pivotally mounting the damper, and balancing means carried by the damper, said casing having openings in each end thereof so disposed as to swing the damper in open position by suction drawing air through the casing and to close the damper by air pressure in excess of the suction.

5. An air controlling means comprising a casing, a vertical wall mounted within the casing and dividing the casing into two chambers, said inner wall having a longitudinally extending opening therethrough in substantially the center thereof, a damper mounted in said opening and having the opposite edges thereof normally engaged with the side walls of the casing, means for balancing the damper, said casing having openings in the end walls thereof communicating with the chambers, the openings in one end wall being reverse from the other end wall whereby to swing the damper into opened position by suction of air from one end and to automatically swing said damper into closed position upon increase in the air pressure on the opposite end in excess of the suction.

In testimony whereof I hereunto affix my signature.

VILLIAM A. HANNUM. 

